permafrost

noun

per·​ma·​frost ˈpər-mə-ˌfrȯst How to pronounce permafrost (audio)
: a permanently frozen layer at variable depth below the surface in frigid regions of a planet (such as earth)

Examples of permafrost in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Meltwater from the mountain’s glaciers and thawing permafrost flows down through ancient channels, fueling the great rivers and soaking into these sprawling boglands. — Literary Hub, 16 Oct. 2026 Chuuraa Evgenia Arbugaeva (UK 2026, 18 min) A Sakha scientist journeys into Siberia’s melting permafrost, where the past emerges alongside ancestral beliefs. — Matthew Carey, Deadline, 14 Oct. 2026 For example, greenhouse gas emissions from melting permafrost, wildfires, or other natural sources, which are all triggered by the temperatures associated with global warming, could essentially become a cycle that fuels itself. — Emily Mae Czachor, CBS News, 14 Oct. 2026 The mysterious death of a lab worker at a plague research institute in Siberia drew global attention to a region where disease risks run as deep as the permafrost. — Mary Ilyushina, Washington Post, 14 Oct. 2026 See All Example Sentences for permafrost

Word History

Etymology

permanent + frost

First Known Use

1943, in the meaning defined above

Time Traveler
The first known use of permafrost was in 1943

Rhymes for permafrost

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Browse Nearby Words

permaculture
permafrost
permalloy
See all Nearby Words

Cite this Entry

“Permafrost.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/permafrost. Accessed 20 Oct. 2026.

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Kids Definition

permafrost

noun
per·​ma·​frost ˈpər-mə-ˌfrȯst How to pronounce permafrost (audio)
: a permanently frozen layer at variable depth below the surface in frigid regions of a planet (as earth)

More from Merriam-Webster on permafrost

Britannica.com: Encyclopedia article about permafrost

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